Electric rail connector



March 3, 1942.

R. s. JAMES ELECTRiC RAIL CONNECTOR Fild Dec.

Patented Mar. 3, 1942 ELECTRIC RAIL CONNECTOR Robert Sloan James, Pittsburgh, Pa. Application December 5, 1940, Serial No. 368,585

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3'70 0. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or for the Government of the United States for governmental purposes without the payment to me of any royalty thereon in accordance' with the provisions of the act of April 30, 1928 (ch. 460, 45 Stat. L. 467).

This invention relates to the means and method whereby conductors for electricity may be electrically connected to rails for railway track circuits, for tying into a track circuit as a source of power, and for grounding purposes.

The present invention is of particular utility in mines and is believed to provide greater safety and efficiency than conventional types of electric rail connectors, such as the rail or ground clamps now in use.

The present invention aims to provide an expeditious manner as well as the means for making good electrical connection to the rail or ground side of a power circuit for the operation of electrically driven equipment. The invention may also be used merely as a means of grounding handheld or other electrically operated machinery to safeguard operators against electric shocks.

In order to secure conventional types of rail connectors, a drilling of the rail to bolt the connector thereto is most generally required, and in other instances a welding operation is required. In still other instances excavation is necessary in order to apply connectors to rails.

It is an object of the present invention to provide a conductor rail-connector which may be readily attached and detached Without rail drilling, bolting to the rail, welding, or excavation. The object of obtaining a good electrical contact with a rail is accomplished by expandingly forcing a connector into the under and upper faces of the rail head and rail flange, respectively.

In developing the invention, it was established that the present invention provides a good electrical contact since the rust or oxide of the rail is penetrated, and also that the connector will hold satisfactorily against jerks on the conductor cables and that the connector is of a construction which is not likely to be damaged since it does not project above the rail and need not project from the side of the rail beyond the width of the rail head.

Other objects and advantages will appear as the description of the particular embodiment selected to illustrate the invention progresses and the novel features of the invention will be particularly pointed out in the appended claims. An embodiment having the characteristics of the invention and by which the same may be practiced is illustrated in side elevation in the accompanying drawing.

The physical embodiment selected to illustrate the invention is shown as applied to the side of a rail between the rail headi and the rail flange 2 and comprises separably mounted burred, sharpened or apexed members, which, for illustrative purposes, are shown as points 3 and 4, of hardened metal which are reversely disposed and preferably spaced in axial alignment. These sharpened members are carried by means whereby they may be forced from each other into the under and upper faces 5 and 6 of the rail head i and flange 2, respectively, for the attachment of the device and .whereby they may be retracted for detachment. The expanding means whereby the apices of the sharpened members 3 and 4 may be forced under compression, i. e., when resisted by the rail members I and 2, through the rust and oxide of the rail surfaces and into penetrating or biting relation with the rail members, for good contact and holding purposes, may comprise screw, wedge, lever, cam or other arrangements such as a compression turnbuckle, jack screws coupled by a right-andleft nut or some simpler effective arrangement such as shown in the drawing for exemplification.

The arrangement shown for forcibly expanding the points to lengthen the space therebetween and cause the apices of the members. 3 and 4 to penetrate the rail surfaces, comprises a bolt 1, from the head 8 of which the penetrating member 3 projects, and a cap-type of nut 9, from which the sharpened member 4 projects. The bolt head 8 and cap 9 may be termed holders for the penetrating points. The bolt head and nut may also be provided with shoulders for engagement by a wrench, or other tool, or may be provided with side sockets in into which pin-, rod-, or lever-like tools I l and I2 may be inserted for rotating the one with respect to the other to force the points of the members 3 and 4 into the inner face of the rail head and flange.

In this \type of means for expandingly forcing the apices of the members 3 and 4 into the metal of the rail, it is preferable that the points be conical since at least one of their holder members, 8 or 9, must be rotated during the expansion and retraction operations.

For installation, the expansion operation is simply an unscrewing of the nut 9 from the threads of the bolt 1, and for detachment the nut is simply run-down on the threads of the bolt to retract the biting points from the sockets formed in the rail surfaces by the compressional installation action.

A lock, such as a lock-nut, may be provided to hold the parts in position if necessary, and combinations of left and right hand threads may be used to provide greater separation of the points for a given travel of the handle or tool used for the rotation of the members.

Cable or other electrical conductors may be connected to any desired part of the device, depending upon conditions under which it is to be used. The terminal I 3 of a cable or other conductor may be connected to the rail connector device by brazing, soldering, welding, or other means, such as by a screw or bolt M threaded into a socket in the bolt head 8 and/or nut 9.

It is also within the scope of my invention to provide combinations of connector elements so mounted or constructed as to be electrically insulated from one another. The use of such cannectors would be beneficial where more than one ground connection is required, as in the case of a hand-held drill where the extra ground connection is usually required to safeguard the operator from electric shocks.

It is believed obvious from the illustrative device and from what has been stated that connectors of the present invention may be made of any desired size in order to be applicable to rails of diiferent size, and may be of such dimension as not to project, when applied to the rail, beyond the width of the rail head in order that the rail head may serve as a protector or shield against accidental jars or jolts which may tend to loosen the connector or destroy its eifective hold. As stated hereinbefore the members 3 and 4 may be of any desired shape or construction so long as a good biting surface is provided when they are compressionally forced against the surface of the rail head and flange.

The invention resides not alone in the structural means for electrically bonding to a rail but in the method which comprises sharpening the reverse ends of a separable or expandable conducting member, positioning the member between the rail head and the rail flange to one side of the rail web, conipressionally forcing the apices of the sharpened ends into the metal of the under portion of the rail head and the upper portion of the rail flange, respectively, by forcibly separating or expanding the conducting member, and securing a conductor conductively to the conducting member.

Having described my invention and illustrated a practical embodiment whereby the same may be practiced, what I claim is:

1. A device for making electrical contact with a steel rail having a rail head and rail flange utilized as a conductor in a transmission system, said device comprising a pair of electrically conductive members having cooperating male and female threaded portions and each having a sharpened portion of hard steel extending reversely outward from said members when journaled and with their apices substantially coaxial with said threaded portions, whereby said sharpened portions may be axially forced penetratingly into and withdrawn from the under and upper surfaces of a rail head and rail flange respectively by rotation of one of said members with respect to the other, and means for securing an end of an electrically conductive lead to one of said members.

2. An electrical rail connector for making electrical contact with a steel rail of the type having opposed flange-like members and utilized as a conductor in a transmission system, said connector comprising a screw jack adapted to be inserted between the opposed fiange-like members of said rail, said screw jack including a pair of members having an axis of relative rotation with respect to each other, means projecting axially from one member of said screw jack for engagement with one of said opposed flange-like members, a tapercd steel contact point of circular cross-section projecting axially from and rotatable with the other member of said screw jack for boring penetration into the other of said opposed flange-like members on rotative advancement, means whereby the member of said screw jack from which said contact point projects may be rotated with respect to and on an axis with the other member of said screw jack to cause said point to rotatingly advance and wipingly penetrate said other opposed fiange-like member, and a terminal electrically connected to said contact point.

ROBERT SLOAN JAMES. 

